High Moisture Content Of The Red Sandstone Mud Slag Hole Study On Road Improved Soil Mechanical Properties

When the tunnel is excavated by milling in the red sandstone stratum,the produced slag have high water content,mud shape and poor engineering properties,so it can only be abandoned,which is costly and easy to cause irreversible damage to the environment.In order to get a kind of economical and practical red sandstone mud hole slag recycling technology,the paper select Ganzhou municipal engineering tunnel of red sandstone mud hole slag as the research object,design the improvement scheme,slag hole will improve soil used as roadbed filler,and the way of improved soil with performance and mechanical properties is studied,the main research contents and results are as follows:（1）The basic physical and mechanical properties of the red sandstone mud-caving slag are obtained by laboratory test.It was judged that the red sandstone mud-caving slag still had disintegration and belonged to the category of over-wet soil,with poor mechanical properties,which provided a reference for the subsequent design of improvement scheme.（2）The water-reducing test compared the effects of different water-reducing agents,analyzed and designed an improvement plan for the red sandstone muddy cave slag.Carried out compaction test,load-bearing ratio test,unconfined compression test and water stability test,and analyzed the road performance of red sandstone muddy cave slag improved soil.The results show that the modified soil formed by adding lime and cement to the red sandstone mud cave slag has high structural strength and water stability,which can meet the requirements of road use.（3）Based on the uniaxial compressive stress-strain curve of red sandstone muddy cave slag,combined with Logistic model function and concrete stress-strain constitutive equation,a stress-strain constitutive equation suitable for improving red sandstone muddy cave slag is proposed,and the data is fitted The results show that the accuracy is high;at the same time,the characteristic parameters of the stress-strain curve(peak stress,peak strain,energy absorption and deformation modulus E₅₀)of cement content,curing age and compaction degree of red sandstone muddy cave slag modified soil are analyzed.Statistical analysis of the characteristic parameters of the stress-strain curve of the red sandstone muddy cave slag modified soil.（4）Based on the road performance test data of the red sandstone muddy cave slag modified soil,use ABAQUS to establish a three-dimensional subgrade solid model,and simulate and analyze the dynamic response of the modified soil subgrade under vehicle load and the cumulative settlement of cyclic loading.The results show that the improvement The treatment can reduce the displacement and acceleration response of the red sandstone muddy cave slag subgrade,and reduce the settlement displacement.